A year ago, when the Offshore Technology Conference came to town, BP’s Macondo well was still gushing thousands of barrels of oil a day into the Gulf of Mexico, and the weight of the disaster hung heavy in the air. On Monday, when this year’s show begins, the mood should be different. Offshore officials say a sense of optimism is returning to the business after a tumultuous year, thanks in part to the recent resumption of drilling in the deep-water Gulf and $100-plus oil prices that are boosting the incentive to explore worldwide. But at OTC, one of the world’s largest gatherings of offshore professionals, the Deepwater Horizon tragedy is still likely to loom large — in presentations, technical papers and sales pitches on the exhibit floor. The overriding message: The industry has learned from the crisis and has emerged the better for it. “I think people are just really re...